He also denies 18 counts of causing grievous bodily harm with intent on 18 patients, including the two dead men.

The offences were allegedly committed between 4 December 2003 and 5 February 2004.

The alleged victims were admitted to A&E with mostly non-life-threatening conditions.

They then all suffered unexplained respiratory arrests, requiring emergency resuscitation, the court heard.

Medical experts later agreed that various drugs and other substances, including muscle relaxants used to paralyse patients for surgery, had been administered to deliberately stop them breathing, Mr Austin-Smith said.